This invention relates to the construction of swimming pools and the like and, more particularly, to a method and apparatus for securing a horizontal row of tiles in alignment to a swimming pool wall along the upper edge portion thereof.
Swimming pools designed to be permanently erected typically are formed by excavating a hole in the ground generally following the contours desired for the pool, and then lining the hole with reinforcing steel on top of which a cement mixture is sprayed to form a concrete bottom and concrete side walls. A thickened concrete portion, referred to in the art as a "bond beam," is provided around the pool at the top of the side walls to structurally define the peripheral edge of the pool and tie the pool side walls together. After the concrete forming the pool side walls and bond beam has cured sufficiently, the cavity defining faces of the concrete walls and of the bond beam are covered with a suitable finishing material.
In the past, it was common to finish the interior wall surfaces of a swimming pool with ceramic tile or the like. However because of the present high costs for material and labor associated with laying tile, it is now more common to face most of the interior of the pool with a finishing coat of a fine aggregate concrete. It is generally necessary, though, to provide at least a single horizontal row of tile adjacent the upper edge portion of the pool side walls at the elevation at which the water level is to be maintained in the pool. The reason for such tile band is that body oils collect along the water surface in a swimming pool and tend to adhere to any concrete at the water level with considerable tenacity and stain the same. The hard, substantially impervous finish provided by a bond of glazed ceramic tiles at the water level, though, facilitates removal of such oils and other matter.
The tile laying or setting procedure now universally followed is for a tile setter to locate the highest elevation along the pool wall and then patch or fill the upper edge of the pool wall to bring it to this elevation. An elongated ledge board is then fixed to the face of the pool wall parallel but below the water line desired in the finished pool. A suitable mortar is then prepared, spread along the proposed pool water line above the ledger board, and each block of tile is seated upon the ledger board and pressed into the mortar. Care is taken during the setting of the tile to align adjacent tiles horizontally in a desired orientation relative to one another, i.e., to make a straight or curved row. The surface of the ledger board on which the tile blocks are seated acts to align the tiles vertically with respect to one another. After the mortar has set, the ledger board is stripped from the wall, and the wall surfaces below the tile band are covered with a concrete finishing material as previously stated.
The above procedure is generally satisfactory for solid ceramic tile blocks capable of supporting themselves and, hence, capable of being supported from below by the ledger board. It will be appreciated, however, that ledger board support, per se, is largely ineffective for properly locating tiles which are not self-supporting. In this connection, for aesthetic reasons many customers desire that the tile band be formed by a mosaic of smaller tiles. Such mosaic tile are typically sold with a flexible backing sheet securing a plurality of the same together in a rectangular pattern with uniform spacing between adjacent tiles. The backing sheet is normally in the form of a web which enables the mortar used to secure the same to a pool face to directly contact the individual tiles. Because such a sheet of mosaic tile is not self-supporting, i.e., will not maintain a planar relationship when supported solely along its bottom edge, various auxiliary supporting arrangements have been provided to maintain the tile in a planar relationship so that it can be supported by a ledger board. For example, reference is made to my U.S. Pat. No. 3,850,404 issued Nov. 26, 1975 for TILESETTING APPARATUS which describes a rigid backing structure which is utilizable with mosaic tile sheets to provide rigidity thereto for appropriately aligning and securing the same to a pool wall. It is desirable, however, to simplify the securence of tile, particularly mosaic tile sheets, in a properly aligned horizontal row to the face of a pool bond beam, i.e. adjacent the upper edge of the pool side wall.